8141652 : Rename methods Objects.nonNullElse* to requireNonNullElse*

[Chris Hegarty]

On 10 Nov 2015, at 18:55, Roger Riggs <Roger.Riggs at oracle.com> wrote:

> A few of the proposed replacements of ?: with requireNonNullElse were unsuitable
> because in the particular context, null is an allowed replacement value.
> 
> The webrev has been updated to revert changes:
> - two uses in jdk/src/java.base/share/classes/java/time/format/DateTimePrintContext.java (Line 145 and 160)
> - src/java.base/share/classes/java/time/temporal/TemporalQueries.java - reverted all changes
> 
> webrev:
> http://cr.openjdk.java.net/~rriggs/webrev-require-non-null-8141652/

Overall looks good.

I’m not sure it is worth adding an instance field, zeroAliases, to Charset?

-Chris.

> 
> Thanks, Roger
> 
> p.s. the previous webrev is renamed: http://cr.openjdk.java.net/~rriggs/webrev-require-non-null-8141652-v1/
> 
> 
> 
> On 11/9/2015 2:35 PM, Roger Riggs wrote:
>> Hi Stephen,
>> 
>> On 11/6/2015 10:42 PM, Stephen Colebourne wrote:
>>> Seems fine to me.
>>> 
>>> I would have inlined the ZoneId change to one line:
>>> String id = Objects.requireNonNullElse(aliasMap.get(zoneId), zoneId);
>>> to avoid the local variable change, but no big deal.
>>> Stephen
>> 
>> Thanks, I'll fix that.
>> 
>> Roger
>>> 
>>> 
>>> 
>>> On 6 November 2015 at 20:24, Roger Riggs <Roger.Riggs at oracle.com> wrote:
>>>> Please review the renaming of java.util.Object methods, the new method names
>>>> are:
>>>>     public static <T> T requireNonNullElse(T obj, T defaultObj);
>>>>     public static <T> T requireNonNullElseGet(T obj, Supplier<? extends T>
>>>> supplier);
>>>> 
>>>> The only remaining possible gotcha for developers is the requireNonNull(T,
>>>> String)
>>>> method that might be confused with requireNonNullElse(T, T). The longer
>>>> name is probably the one you want.
>>>> If you see a value that looks like an exception string, you've got the wrong
>>>> method.
>>>> 
>>>> To validate some of the uses, I visually scanned src/java.base looking
>>>> expressions of the pattern   (e1 != null) ? e1 : e2
>>>> Most uses of the ternary operator involve either primitive types or
>>>> conditions other than != null;
>>>> quite a few involved returning null and so were not appropriate to be
>>>> converted.
>>>> 
>>>> 10 files contained relevant expressions:
>>>>  - 2 should be using Objects.toString() to provide a default value for a
>>>> String.
>>>>  - 2 can use the requireNonNullElseGet form to delay evaluating the
>>>> alternative value.
>>>>      (2 others were too early in the boot cycle to use lambda).
>>>>  - The rest followed the expected pattern; though checking if throwing an
>>>> exception was extra work.
>>>> 
>>>> Please review and comment.
>>>> 
>>>> Webrev:
>>>> http://cr.openjdk.java.net/~rriggs/webrev-require-non-null-8141652/
>>>> 
>>>> Thanks for the detailed evaluation and discussion.
>>>> 
>>>> Roger
>>>> 
>> 
>